dramatic warning about an ingredient still present in so many favorite americans foods. Transfats. You've heard the term and probably know you should be careful. Today the fda issueed a stark warning. No amount of transfat, no matter how small is safe. They say banning it all together will save lives. How many? Dr. Richard besser tells us. Reporter:7,000 lives a year, that's how many people the fda estimates will be saved if they do it. Banned from america's food all transfats and other partially hydrogenated oils. It would mean many of the foods america loves would have to change. From this frozen marie calendar pie to pop secret butter popcorn to frozen pizza and white castle frozen sliders. This is a dangerous substance that people shouldn't be consuming. They have long been used to keep processed foods fresher longer. That is correct da they can damage your heart. Causing heart attacks. A lot of food makers have reduced these oils over the years. Until the ban takes place how can you stop it? Remember transfats are a type of pho. The label, like this chris co, says zero transfat. Look closely. There is still partially hydrogenated oil in there. Chris co told abc news today they're phasing that out, too. Food makers are allowed to say zero transfat if there is less than half a gram per serving. Right now there is no REGULATIONS ON PHOs. They're saying these aren't just unhealthy. They're unsafe at any level. So watch for hydrogenated or partial lie high draj natd in the label. That's what you have to look for.

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